Find free room (booking system)

Question

For a booking system I have a table with rooms, arrival and departure.

Example data:

id | room | arrival    | departure
---+------+------------+-----         


        

Answer 1

You could also use the BETWEEN comparison operator for this purpose. In this case you would do something like this:

SELECT r.id FROM room r WHERE r.id NOT IN
(
    SELECT rb.room FROM room_booking rb WHERE 
        ('2011-03-10' BETWEEN rb.arrival AND rb.departure) OR 
        ('2011-03-12' BETWEEN rb.arrival AND rb.departure)
)